Tone Generator

How the tone generator works

Press Play and the tone starts instantly, synthesized live with the Web Audio API. Drag the frequency slider, type an exact value in the box, or nudge it with the −1 Hz / +1 Hz and ×½ / ×2 buttons. The nearest note name (equal temperament, A4 = 440 Hz) appears under the readout, so the tool doubles as a tuning reference.

• Presets jump straight to 40 Hz, 100 Hz, 440 Hz (concert A), or 1 kHz (reference tone).
• Waveform switches between sine (a pure tone), square, triangle, and sawtooth. Non-sine waves sound louder at the same gain, so the level is trimmed automatically when you switch.
• Volume starts at a moderate 30%, and playback fades in and out so it never clicks when you start or stop.

Typical uses: tuning instruments, finding the resonant frequency of a room or an object, testing how low your subwoofer goes or how high your tweeters reach, and checking which frequencies you can still hear.

Hearing and speaker safety. Loud tones can damage both. Find a comfortable level with a 1 kHz tone first, then stay near it — especially in the high range, where turning the volume up to hear a faint tone is the easiest way to hurt your ears. Nothing is recorded or uploaded; everything runs on your device.